All sugars ain't sweet: selection of particular mono-, di- and trisaccharides by western carpenter ants and European fire ants

Ants select sustained carbohydrate resources, such as aphid honeydew, based on many factors including sugar type, volume and concentration. We tested the hypotheses (H1–H3) that western carpenter ants, Camponotus modoc, seek honeydew excretions from Cinara splendens aphids based solely on the presence of sugar constituents (H1), prefer sugar solutions containing aphid-specific sugars (H2) and preferentially seek sugar solutions with higher sugar content (H3). We further tested the hypothesis (H4) that workers of both Ca. modoc and European fire ants, Myrmica rubra , selectively consume particular mono-, di- and trisaccharides. In choice bioassays with entire ant colonies, sugar constituents in honeydew (but not aphid-specific sugar) as well as sugar concentration affected foraging decisions by Ca. modoc . Both Ca. modoc and M. rubra foragers preferred fructose to other monosaccharides (xylose, glucose) and sucrose to other disaccharides (maltose, melibiose, trehalose). Conversely, when offered a choice between the aphid-specific trisaccharides raffinose and melezitose, Ca. modoc and M. rubra favoured raffinose and melezitose, respectively. Testing the favourite mono-, di- and trisaccharide head-to-head, both ant species favoured sucrose. While both sugar type and sugar concentration are the ultimate cause for consumption by foraging ants, strong recruitment of nest-mates to superior sources is probably the major proximate cause.

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Know your foe: synanthropic spiders are deterred by semiochemicals of European fire ants

Royal Society Open Science ◽

10.1098/rsos.210279 ◽

2021 ◽

Vol 8 (5) ◽

pp. 210279

Author(s):

Andreas Fischer ◽

Yerin Lee ◽

T'ea Dong ◽

Gerhard Gries

Keyword(s):

Filter Paper ◽

Fire Ants ◽

Deterrent Effect ◽

Lasius Niger ◽

Community Members ◽

Black Widow ◽

Latrodectus Hesperus ◽

Ant Colonies ◽

Carpenter Ants ◽

Web Building

Many ants prey on spiders, suggesting that web-building spiders may avoid micro-locations near ant colonies or frequented by foraging ants. Here we tested the hypothesis that ant-derived semiochemicals deter synanthropic spiders. To generate stimuli, we exposed filter paper for 12 h to workers of European fire ants, Myrmica rubra, black garden ants, Lasius niger, or western carpenter ants, Camponotus modoc , and then offered select urban spiders in three-chamber olfactometer bioassays a choice between ant-exposed filter paper and unexposed control filter paper. Semiochemical deposits of M. rubra , but not of L. niger or C. modoc , had a significant deterrent effect on subadults of the false black widow, Steatoda grossa, the black widow, Latrodectus hesperus , and the hobo spider, Eratigena agrestis, as well as a moderate (but statistically not significant) deterrent effect on the cross spider, Araneus diadematus . The deterrent effect caused by semiochemical deposits of M. rubra may be attributable to the aggressive nature and efficient foraging of M. rubra in its invaded North American range, exerting selection pressure on community members to recognize M. rubra semiochemicals and to avoid micro-locations occupied by M. rubra .

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Flower mites decrease nectar availability in the rain-forest bromeliad Neoregelia johannis

Journal of Tropical Ecology ◽

10.1017/s0266467410000179 ◽

2010 ◽

Vol 26 (4) ◽

pp. 373-379 ◽

Cited By ~ 2

Author(s):

Tadeu J. Guerra ◽

Gustavo Q. Romero ◽

Woodruff W. Benson

Keyword(s):

Rain Forest ◽

Sugar Content ◽

Sugar Concentration ◽

Production Rates ◽

Nectar Production ◽

Nectar Volume ◽

Bombus Morio ◽

Nectar Rewards ◽

Flower Mites ◽

Nectar Availability

Abstract:Nectarivorous flower mites can reduce the volume of nectar available to pollinators. The effects of the flower mite Proctolaelaps sp. on nectar availability in flowers of a melittophilous bromeliad Neoregelia johannis (Bromeliaceae) was evaluated in a coastal rain forest in south-eastern Brazil. In a randomized block experiment utilizing 18 flower pairs, one per bromeliad ramet, pollinators (Bombus morio) and mites were excluded, and then nectar volume, sugar concentration and sugar mass were quantified over the anthesis period. Mites significantly reduced nectar volume early in the morning (6h00–8h00), but not later (10h00–12h00). Mites decreased total volume of nectar available up to 22%. Sugar concentration in nectar was higher earlier in the morning, and decreased between 10h00–12h00. The pronounced consumption of nectar by mites during the period of higher sugar concentration reduced the total amount of sugar available to pollinators by 31%. This is the first study showing that flower mites decrease nectar rewards in a melittophilous plant. Because nectar volume by itself incompletely describes nectar production rates and the effects of nectar removal by flower mites on the availability of sugar, our study highlights the inclusion of sugar content in future studies assessing the effects of thieves on nectar production rates.

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ADDITIONAL CRITERIA FOR SELECTION OF MALTING QUALITY IN BARLEY BREEDING

Canadian Journal of Plant Science ◽

10.4141/cjps76-131 ◽

1976 ◽

Vol 56 (4) ◽

pp. 805-809 ◽

Cited By ~ 2

Author(s):

V. M. BENDELOW

Keyword(s):

Specific Gravity ◽

Filtration Rate ◽

Sugar Content ◽

Reducing Sugar ◽

Malting Quality ◽

Breeding Programs ◽

Barley Breeding ◽

Sample Extraction ◽

Criteria For Selection ◽

Selection Of

A procedure that provides information on the suitability of barley for malting and, brewing purposes is described. Three parameters are measured: mash filtration rate, wort viscosity and wort-reducing sugar content, as maltose. Maltose is determined by an auto-analyzer method and this is a satisfactory alternative to the specific gravity procedure for the estimation of percent extract. The addition of these criteria to those already in use enables more discriminatory selection at early generations of barley-breeding programs. The technique requires only one sample extraction and 18 g of laboratory malt.

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Linguistic Divergence and the Collapse of Preclassic Civilization in Southern Mesoamerica

American Antiquity ◽

10.2307/281790 ◽

1987 ◽

Vol 52 (2) ◽

pp. 367-382 ◽

Cited By ~ 5

Author(s):

Bruce H. Dahlin ◽

Robin Quizar ◽

Andrea Dahlin

Keyword(s):

Material Culture ◽

Communication Networks ◽

Classic Period ◽

Late Classic ◽

Postclassic Period ◽

Proximate Cause ◽

Terminal Classic ◽

Early Postclassic ◽

Ultimate Cause ◽

Early Classic Period

Based on published lexicostatistical dates, two intervals in the prehistory of southern Mesoamerica stand out as fertile periods in terms of the generation of new languages: the Terminal Preclassic/early Early Classic Periods, and the Early Postclassic Period. After comparing archaeological evidence with language distributions within the subregions of southern Mesoamerica during the first of these periods, we conclude that the cultural processes during both periods had the same potential for producing rapid rates of linguistic divergences. Just as rapid proliferation of linguistic divisions was symptomatic of the well-known collapse of Late Classic Maya civilization, so it can be taken as a sign of a collapse of Terminal Preclassic civilization. Both collapses were characterized by severe population reductions, site abandonments, an increasing balkanization in material culture, and disruption of interregional communication networks, conditions that were contributory to the kind of linguistic isolation that allows language divergences. Unlike in the Terminal Classic collapse episode, small refuge zones persisted in the Early Classic Period that served as sources of an evolving classicism; these refuge zones were exceptions, however, not the rule. Although the collapse of each site had its own proximate cause, we suggest that the enormous geographical range covered by these Early Classic Period site failures points to a single ultimate cause affecting the area as a whole, such as the onset of a prolonged and devastating climatic change.

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Effects of menu labelling on students′ food choice: a preliminary study

British Food Journal ◽

10.1108/bfj-03-2018-0188 ◽

2019 ◽

Vol 121 (2) ◽

pp. 479-491 ◽

Cited By ~ 1

Author(s):

Greta Krešić ◽

Nikolina Liović ◽

Jelka Pleadin

Keyword(s):

Positive Impact ◽

Food Selection ◽

Sugar Content ◽

Daily Intake ◽

Nutrition Knowledge ◽

Grocery Store ◽

Nutrition Label ◽

Content Type ◽

Menu Selection ◽

Selection Of

PurposeThe purpose of this paper is to assess the relationship between nutrition knowledge and grocery store nutrition label use, with using nutrition information disclosure on menu selection in a group of hospitality management students, who shall be responsible for menu labelling in their future careers.Design/methodology/approachA between-subject design included 324 students, who were randomly assigned to choose from a menu labelled as follows: unlabelled; kcal label only; graphical label providing information on the per cent of the recommended daily intake of energy and four nutrients. Their nutrition knowledge and habit of reading grocery store nutrition labels were tested using an additional questionnaire.FindingsThe results showed that the provision of energy value information resulted in the selection of less energetic, less fat and less salted food, while a graphical label additionally led to the selection of food having a lower saturated fatty acid (SFA) and sugar content. Multiple regression analysis showed that the habit of packaged food nutrition label reading was a significant predictor of choosing food having a lower energy (p<0.001), fat (p<0.001), SFA (p<0.001), sugar (p<0.001) and salt (p=0.003) content, while the influence of nutrition knowledge on food selection was proven insignificant.Originality/valueGiven the established positive impact of menu labelling, these findings support the future European policy mandating energy and nutrient content disclosure on menus, but also point to the need for more-intense consumer education.

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Seed Ontogeny and Nonstructural Carbohydrates of Cycas micronesica Megagametophyte Tissue

HortScience ◽

10.21273/hortsci10986-16 ◽

2016 ◽

Vol 51 (9) ◽

pp. 1144-1147 ◽

Cited By ~ 3

Author(s):

Thomas E. Marler ◽

Nirmala Dongol

Keyword(s):

High Pressure ◽

Biological Function ◽

Starch Content ◽

Sugar Content ◽

Dry Weight ◽

Field Work ◽

Weight Basis ◽

Sugar Concentration ◽

Nonstructural Carbohydrates ◽

Starch Concentration

The profile of nonstructural carbohydrates (NSC) was quantified to determine sugar and starch relationships of megagametophyte tissue during Cycas micronesica K.D. Hill seed ontogeny. Field work occurred in northern Guam where megastrobili were marked and dated as they emerged from stem apices of plants in a natural population. Seeds were harvested beginning 6 months after megastrobili emergence and continuing until 28 months, and gametophyte tissue was separated from the remainder of each seed. Carbohydrates within lyophilized gametophyte tissue were quantified by high-pressure liquid chromatography. The levels of glucose and fructose declined from a high at 6 months to a homeostasis at 11 months, and the levels of sucrose similarly declined from 6 months to a homeostasis at ≈14 months. Starch content exceeded sugar content and increased from 6 months to reach a homeostasis at ≈18 months. Maltose was not detected in any sample. Stoichiometric quotients changed dramatically until ≈14 months, when they became fairly stable until 28 months. Starch concentration was ≈5-fold greater than sugar concentration at 6 months, and increased to ≈15-fold greater than sugar concentration by 28 months. Total NSC in mature megagametophytes was almost 70% on a dry weight basis. Our results are in agreement with the biological function of this haploid tissue, as copious carbohydrate resources are readily available to support embryo and seedling growth.

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Potential for Use of Erythritol as a Socially Transferrable Ingested Insecticide for Ants (Hymenoptera: Formicidae)

Journal of Economic Entomology ◽

10.1093/jee/toaa019 ◽

2020 ◽

Vol 113 (3) ◽

pp. 1382-1388 ◽

Cited By ~ 1

Author(s):

Meghan Barrett ◽

Virginia Caponera ◽

Cheyenne McNair ◽

Sean O’Donnell ◽

Daniel R Marenda

Keyword(s):

Social Insect ◽

Fire Ants ◽

Dependent Manner ◽

Agricultural Pests ◽

Concentration Dependent Manner ◽

Ant Colonies ◽

Ad Libitum ◽

Ant Control ◽

Imported Fire Ants ◽

Red Imported Fire Ants

Abstract Ants are significant structural and agricultural pests, generating a need for human-safe and effective insecticides for ant control. Erythritol, a sugar alcohol used in many commercial food products, reduces survival in diverse insect taxa including fruit flies, termites, and mosquitos. Erythritol also decreases longevity in red imported fire ants; however, its effects on other ant species and its ability to be transferred to naïve colony members at toxic doses have not been explored. Here, we show that erythritol decreases survival in Tetramorium immigrans Santschi (Hymenoptera: Formicidae) in a concentration-dependent manner. Access to ad-libitum water reduced the toxic effects of erythritol, but worker mortality was still increased over controls with ad-lib water. Foraging T. immigrans workers transferred erythritol at lethal levels to nest mates that had not directly ingested erythritol. Similar patterns of mortality following erythritol ingestion were observed in Formica glacialis Wheeler (Hymenoptera: Formicidae), Camponotus subarbatus Emery (Hymenoptera: Formicidae), and Camponotus chromaiodes Bolton (Hymenoptera: Formicidae). These findings suggest that erythritol may be a highly effective insecticide for several genera of ants. Erythritol’s potential effectiveness in social insect control is augmented by its spread at lethal levels through ant colonies via social transfer (trophallaxis) between workers.

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La nécessité d'un programme d'amélioration de certaines essences forestières feuillues : Applications aux genres Juglans et Acer

The Forestry Chronicle ◽

10.5558/tfc45386-6 ◽

1969 ◽

Vol 45 (6) ◽

pp. 386-392 ◽

Cited By ~ 1

Author(s):

L. Parrot

Keyword(s):

Acer Saccharum ◽

Sugar Content ◽

Coniferous Forest ◽

Tree Breeding ◽

Common Species ◽

Breeding Programs ◽

Short Term Study ◽

Wood Sculpture ◽

The One ◽

Selection Of

Although most of our tree-breeding programs are concerned with coniferous forest species, we must not neglect the valuable hardwoods exploited in our region. The need of these programs for hardwoods is undeniable and they should be based, as much as possible, on genecological studies.One such study illustrates the wide variation in genetic adaptation of Juglans nigra and indicates its practical implications. Further, these results were obtained from a short-term study of 17 provenances for variations in frost-hardiness at a single location.Intra-specific variation is being investigated in Juglans cinerea, a more common species in our region than the one previously mentioned and one which is also in strong demand for furniture-making and wood sculpture. The resulting data will permit the selection of the best seed zones. Such a breeding program could eventually support far more than small, local industries.Another project involving Acer saccharum describes the variation in sugar-content of sap in three maple stands sampled each spring from 1965 to 1969. Two stands were very homogeneous compared to the third. The magnitude of the differences maintained throughout the study period led to the selection of nine genotypes whose sugar contents varied from 4.6% to 9.7%, indicating maximum genetic gains on the order of 150%.Continued research in vegetative propagation of Acer saccharum is needed for the production of clonal populations for breeding programs.

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